hash_set::rehash (STL/CLR)

 

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The latest version of this topic can be found at hash_set::rehash (STL/CLR).

Rebuilds the hash table.

Syntax

void rehash();  

Remarks

The member function rebuilds the hash table, ensuring that hash_set::load_factor (STL/CLR)() <= hash_set::max_load_factor (STL/CLR). Otherwise, the hash table increases in size only as needed after an insertion. (It never automatically decreases in size.) You use it to adjust the size of the hash table.

Example

// cliext_hash_set_rehash.cpp   
// compile with: /clr   
#include <cliext/hash_set>   
  
typedef cliext::hash_set<wchar_t> Myhash_set;   
int main()   
    {   
    Myhash_set c1;   
    c1.insert(L'a');   
    c1.insert(L'b');   
    c1.insert(L'c');   
  
// display initial contents " a b c"   
    for each (wchar_t elem in c1)   
        System::Console::Write(" {0}", elem);   
    System::Console::WriteLine();   
  
// inspect current parameters   
    System::Console::WriteLine("bucket_count() = {0}", c1.bucket_count());   
    System::Console::WriteLine("load_factor() = {0}", c1.load_factor());   
    System::Console::WriteLine("max_load_factor() = {0}",   
        c1.max_load_factor());   
    System::Console::WriteLine();   
  
// change max_load_factor and redisplay   
    c1.max_load_factor(0.25f);   
    System::Console::WriteLine("bucket_count() = {0}", c1.bucket_count());   
    System::Console::WriteLine("load_factor() = {0}", c1.load_factor());   
    System::Console::WriteLine("max_load_factor() = {0}",   
        c1.max_load_factor());   
    System::Console::WriteLine();   
  
// rehash and redisplay   
    c1.rehash(100);   
    System::Console::WriteLine("bucket_count() = {0}", c1.bucket_count());   
    System::Console::WriteLine("load_factor() = {0}", c1.load_factor());   
    System::Console::WriteLine("max_load_factor() = {0}",   
        c1.max_load_factor());   
    return (0);   
    }  
  

 a b c  
bucket_count
() = 16  
load_factor
() = 0.1875  
max_load_factor
() = 4  
  
bucket_count
() = 16  
load_factor
() = 0.1875  
max_load_factor
() = 0.25  
  
bucket_count
() = 128  
load_factor
() = 0.0234375  
max_load_factor
() = 0.25  

Requirements

Header: <cliext/hash_set>

Namespace: cliext

See Also

hash_set (STL/CLR)
hash_set::bucket_count (STL/CLR)
hash_set::load_factor (STL/CLR)
hash_set::max_load_factor (STL/CLR)